On December 15, 1998, at 1638 mountain standard time, a Piper Malibu PA-46-350P, N9255B, sustained substantial damage during an encounter with turbulence during descent near Granby, Colorado. The airline transport rated pilot and his three passengers were not injured. The airplane was being operated by 101 Jet Aviation, Inc., of Englewood, Colorado, under Title 14 CFR Part 91. Visual meteorological conditions prevailed for this cross-country flight which originated from Idaho Falls, Idaho, approximately 1 hour 24 minutes before the accident. An IFR flight plan had been filed. According to the pilot, "the flight had been uneventful to that point." He said that "he felt the nose tuck a little and then wham--they hit severe/extreme turbulence." The 5 second event rolled the airplane into a 90 degree right bank, and a pitch up attitude of 45 degrees. The pilot reported that his airspeed indicator was reading 140 knots, and his altitude was 15,700 feet at the time of the event. He calculated his maneuvering speed to be approximately 120 knots. Radar data indicated that the airplane gained 500 feet of altitude in 5 to 6 seconds. Additionally, the radar ground tract indicated that the airplane was over Corona Pass when the event happened. Both wings and horizontal stabilizer had to be replaced.